I could ump you could ump she could ump we could ump you could ump they could ump
V-ing form
I could be umping you could be umping she could be umping we could be umping you could be umping they could be umping
Perfect
I could have umped you could have umped she could have umped we could have umped you could have umped they could have umped
V-ing perfect
I could have been umping you could have been umping she could have been umping we could have been umping you could have been umping they could have been umping
Negation
Simple form
I could not ump you could not ump she could not ump we could not ump you could not ump they could not ump
V-ing form
I could not be umping you could not be umping she could not be umping we could not be umping you could not be umping they could not be umping
Perfect
I could not have umped you could not have umped she could not have umped we could not have umped you could not have umped they could not have umped
V-ing perfect
I could not have been umping you could not have been umping she could not have been umping we could not have been umping you could not have been umping they could not have been umping
Interrogative form
Simple form
could I ump? could you ump? could she ump? could we ump? could you ump? could they ump?
V-ing form
could I be umping? could you be umping? could she be umping? could we be umping? could you be umping? could they be umping?
Perfect
could I have umped? could you have umped? could she have umped? could we have umped? could you have umped? could they have umped?
V-ing perfect
could I have been umping? could you have been umping? could she have been umping? could we have been umping? could you have been umping? could they have been umping?
Interro-negative form
Simple form
could I not ump? could you not ump? could she not ump? could we not ump? could you not ump? could they not ump?
V-ing form
could I not be umping? could you not be umping? could she not be umping? could we not be umping? could you not be umping? could they not be umping?
Perfect
could I not have umped? could you not have umped? could she not have umped? could we not have umped? could you not have umped? could they not have umped?
V-ing perfect
could I not have been umping? could you not have been umping? could she not have been umping? could we not have been umping? could you not have been umping? could they not have been umping?